Blackjack proof of concept
* Uses custom palette to show cards in as many colours as possible
* Only basic gameplay.
UPDATE 2021-06-08:
* ENTER (RETURN) also selects option
* Cards fall more naturally
* 8 decks in shoe, cut card at 20 cards. Will shuffle entire shoe when cut card is reached (end of round)
* Splitting pairs (as well as royals). Resplits should work, but untested.
TODO:
* Money and bets
* Doubling down
* Payout Blackjacks immediately